Prof Maninder Agarwal, from IIT Kanpur (IIT-K) who has developed the Sutra mathematical model to predict the trajectory of the Covid pandemic with great accuracy, has now said that there may be no fourth wave in the country.
In an article, Agarwal, a professor in the department of computer science engineering, said that there are two major reasons for this conclusion.
The first reason is the level of natural immunity in the country. Natural immunity is defined as the immunity acquired by a previous infection.
As per the SUTRA model for India, over 90 per cent of India’s population has acquired natural immunity. This is also validated by data from ICMR surveys that have consistently found the actual number of infected people to be more than 30 times the reported numbers, he said.
Natural immunity acts as a strong protection against infection. In an extensive study done for 36 countries across the world covering all continents and more than half of the world’s population, it was found that the severity of the Omicron wave in these countries was inversely proportional to the level of natural immunity present in them.
Secondly, until now, genome sequencing has not shown any significantly new mutant even in NCR. Only variants belonging to the lineage of Omicron, referred to as BA. 2, BA. 2. 9, BA. 2. 10, and BA. 2. 12, have been detected.
This means that immunity acquired against Omicron will continue to hold against all these variants. With more than 90 per cent people in India already immune against Omicron,one does not expect any significant fourth wave.
The reason for increase in number of Covid cases, according to Agarwal, is that all restrictions have all been lifted, and the new variants of Omicron are slightly more infectious.
Both result in faster spread of the virus among the non-immune population, thereby increasing numbers. This increase is not likely to be substantial though.
He stated that vaccination is excellent in preventing serious illness but not particularly good in preventing mild infection by Omicron.
However, the analysis does not imply that vaccination is not required. Vaccines protect against major illness and are extremely useful. Countries that have followed a strict zero-Covid policy are going through a difficult period at present with high infection numbers, for example, South Korea, Hong Kong, and China.
Zero-Covid policy ensures that natural immunity does not build up, leaving the population susceptible to widespread Omicron infection.
He further said the current situation is not a cause of concern. A fourth wave can only come if there is a new mutant that bypasses natural immunity significantly. Of course, certain precautions are advisable.
Uttar Pradesh has proved to be a great example when it comes to Covid management and became the first state to give over 30 crore doses. It has now moved fast by making masks mandatory and has ordered daily testing of over 1 5 lakh samples.
The recovery rate also stands at a good 98.78 per cent.
